Rocker arm ignition device



F. HINZMANN ROCKER ARM IGNITION DEVICE July 16, 1968 2 Sheets-Shet 1 Filed Nov. 21. 1966 INVENTOR F/WFD MAI? fl/MZlV/J/V/V 1M 1k. MW

' July 16, 1968 F. HINZMANN 3,392,671

ROCKER ARM IGNITION DEVICE Filed Nov. 21, 1966 2 Sheets-Sheet 2 INVENTOR FR/ED/Wlfi H/A/ZMA/i/A/ 4AM mnfkma,

AGENT United Smtes Patent ABSTRACT OF THE DISCLOSURE The invention concerns an improved grenade having a fuse which comprises a retaining or locking spring member positioned betweerrthe spring loaded hinged firing pin and the .usual safety guard lever which usually swings in the same direction as the firingpin of the fuse. The locking spring member isprovided at one end with a lug which is inserted into a bore hole in the top of the fuse body. This joint serves as the pivot point of the member. The member has a contour which follows that of the retracted firing pin and of the adjacent part of the safety guard lever. Its free end presses against a .notch in the safety guard lever above the pivot point of the latter. The member retains the firing pin in its initial cocked position until the safety guard lever has swung around by at least about 70 from the body of the grenade and has become detached from the fuse. The member then is swung outwardly on its pivot by the force of the firing pin spring as it swings the firing pin through its firing arc and against the primer.

The present invention relates to a rocker arm ignition device and more particularly to a rocker arm ignition device for projectiles which device is constructed of a springloaded, hinged firing pin and a safety guard lever swinging in the same direction as the firing pin.

Such rocker arm ignition or detonating devices, for instance, for hand grenades, usually consist of a top part which carries the priming composition of the projectile initiator. Ignition of said priming composition or primer is effected by causing a spring-loaded firing pin axially rotatably arranged in the top part of the ignition device, to be released and impelled thereonto. Said firing pin is held under tension by a safety guard lever which onesidedly engages the ignition top part and is hooked thereinto and which is locked and secured to the top part of the ignition or detonating device in its initial position by means of a safety member such as a safety pin.

' When using the projectile, for instance, the hand grenade, the safety member is pulled out of the safety guard lever and the ignition top part. The hand of the person throwing the hand grenade grips and encircles the safety guard lever as Well as the main part of the hand grenade and thus keeps it in secured position. On throwing the hand grenade, i.e. when the throwers hand is opened, first the safety guard lever is forced away from the body of the hand grenade. Thereby, the safety guard lever and the firing pin are caused by the tension of the cocking spring to swing simultaneously around the axes of their respective mountings until the firing pin is released. This position is attained after the safety guard lever has been caused to swing around its axis by about 60. When this position is attained, the firing pin rapidly precedes the safety guard lever and ignites the priming composition by its impact thereon. Thereby, the safety guard lever is fully detached from the hand grenade body due to the tension of the cocking spring and its pivotal attachment to the top part of the hand grenade.

Such an ignition or detonating device, however, is highly 3,392,671 Patented July 16, 1968 unreliable because the safety guard lever may carry out a the above mentioned swinging movement and may thus release the firing pin even if the hand of the thrower is only partly opened although the throwing person may still hold the hand grenade with the pivotally attached safety guard lever in his hand. Since the thrower may readily fail to hear and notice that the firing pin has been released, unintentional and premature ignition and detonation of such hand grenades is possible.

The safety devices provided in hand grenades with a straight-guided firing pin or with a firing pin which is tilted with respect to the primer do not exclude such a premature ignition or detonation on throwing.

It isone object of the present invention to provide a rocker arm ignition device which is free of the disadvantages of the heretofore used ignition devices and in which the safety guard lever releases the firing pin after swinging about its'axis of attachment to the top part of the device by at least 70 and preferably by more than advantageously not before the safety guard lever has become completely detached from the body of the hand grenade.

Other objects and advantageous features of the present invention will become apparent as the description proceeds.

In principle the problem of providing a safe and reliable rocker arm ignition device is solved according to the present invention by arranging under pre-tension a retaining or locking spring member between the spring loaded, hinged firing pin and the safety guard lever swinging in the same direction as the firing pin whereby the retaining or looking spring member swings in opposite direction to the movement of the firing pin and the safety guard lever.

As a result of the arrangement of such a retaining or locking spring member the firing pin is retained and locked in its initial cocked position until the safety guard lever has swung around by at least about 70 and has become detached from the top part of the ignition device. The retaining or locking spring member will be released from its position and will also release the firing pin only when the safety guard lever is completely separated and detached from the hand grenade.

The retaining or locking spring member is provided at one end with a tongue or lug which is freely movably inserted into a bore hole in the top part of the ignition device. This joint is the pivot around which the retaini g or locking spring swings on throwing the hand grenade when the safety guard lever has swung around the above mentioned predetermined angle. The other free end of the retaining or locking spring member is bent upwardly and presses or pushes against the edge of a notch or recess in the safety guard lever in which it is engaged. The advantages of the rocker arm ignition device according to the present invention over heretofore known rocker arm ignition devices with pivotally arranged firing pin will be explained and illustrated more in detail by the attached drawings. Of these drawings:

FIG. 1 illustrates a hand grenade with the heretofore used ignition device, partly in cross-sectional view;

FIG. 2 shows a hand grenade with the ignition device according to the present invention, partly in cross-sectional view;

FIG. 3 illustrates the position of the ignition device according to FIG. 2 with upwardly swung safety guard immediately before ignition, partly in cross-sectional view;

FIG. 4 is a top plan view of the hand grenade with the rocker arm ignition device according to FIG. 2; and

FIGS. 5a and 5b how the retaining or locking spring member in cross-sectional view and in top plan view.

In these figures like index numerals indicate like parts of the rocker arm ignition device according to the present invention.

Top part 2 of the ignition device is screwed on hand grenade body I. Said top part 2 carries the delaying and priming composition 3. Firing pin 4 is pivotally arranged about shaft 5 and is pushed against safety guard lever 7 by tension or cocking spring 6. Safety guard lever 7 is attached to transverse shaft 9 by means of its hook-shaped ends 8 and is kept in its position by safety pin or cotter 10 which is passed through safety guard lever 7 and top part 2 of the ignition device.

When actuating the known ignition device of FIG. 1 and removing safety pin 10, safety guard lever 7 is forced upwardly by the tension of spring 6 of firing pin 4 on opening the hand gripping the hand grenade until the position 7a of said safety guard lever 7 is attained as indicated in FIG. 1. It is evident that firing pin 4 is capable of slipping underneath safety guard lever 7 and of impacting upon primer 3 thus igniting the same. The upward movement of safety guard lever 7 usually continues due to the momentum imparted thereto by the release of firing pin 4 and the tension of spring 6 thus causes said safety guard lever 7 to become detached from shaft 9. FIG. 1 clearly shows that firing pin 4 will slip underneath safety guard lever 7 and will actuate the firing mechanism even if the hand of the grenade thrower is only partly opened and without the safety guard lever 7 being completely detached from the hand grenade.

FIGS. 2 and 4 illustrate the hand grenade with the ignition device according to the present invention when not actuated and FIG. 3 shows said device when actuated, i.e. immediately before ignition of the priming composition.

In said FIGS. 2 to 4 top part 2 of the ignition device is screwed into hand grenade body 1. Said top part 2 carries delaying and priming composition 3. In contrast to the known device of FIG. 1, there is provided retaining or locker spring 11 between firing pin 4 cocked by means of cocking spring 6 and safety guard lever 7. Said locking spring 1 1 is mounted in bore of top part 2 of the hand grenade. Its free end 12 is upwardly bent and pushes against edge 16 of recess 14 provided between the two hook-shaped ends 8 of safety guard lever 7. Said hookshaped ends 8 are engaged around transverse shaft 9 provided in top part 2. When throwing the hand grenade, safety guard lever 7 is caused to rotate and swing around shaft 9 due to the action of locking spring 11 which is under pro-tension. FIG. 3 shows the position of locking spring 11 when it lifts safety guard lever 7 from its mounting. Thereby, said safety guard lever 7 is ejected and detached from the hand grenade in the direction of arrow a. Locking spring 11 can be lifted by firing pin 4 from its mounting in bore 15 only after safety guard lever 7 has been detached. Thereby, said locking spring 7 moves in the direction of arrow b and thus rleases firing pin 4 so that it may impact upon priming composition 3 by moving as indicated by arrow 0.

These figures clearly demonstrate a further characteristic feature of the present invention namely that the path or sweep of firing pin 4 or, respectively the tension of cocking spring 6 are always constant, i.e. independent from the position of safety guard lever 7 at the moment it is detached from the hand grenade. As a result thereof the priming composition is always ignited independently from the position of safety guard lever 7 at the moment the hand grenade is thrown. Due to said constancy of firing pin sweep and cooking spring tension ignition of the priming composition by the same impact energy as well as uniform combustion are always ensured. Misfiring due to too low an impact energy is also avoided.

Of course, the shape andform of retaining and locking spring 11 as shown in the drawings may be varied according to the shape and form of the safety guard lever 7 and its manner of mounting. FIGS. 5a and 5b illustrate a suitable and effective retaining and locking spring -11.

It is also possible to use the igniting device according to the present invention for igniting other projectiles, such as smoke bombs, tear gas bombs, or others.

Of course, many changes and variations in the construction of the safety guard lever, the firing pin, the retaining and locking spring, their mountings and attachment to the top part of the projectile, and the like may be made by those skilled in the art in accordance with the principles set forth herein and in the claims annexed hereto.

I claim:

1. A rocker arm igniting device for igniting the priming composition of a projectile by the impact of a firing pin thereon, said device having a firing pin pivotally mounted on the top part of the projectile carrying the priming composition, a safety guard lever attached to said top part and swinging in the same direction of rotation as the firing pin, the firing pin being forced against the safety guard lever by the action of a cocking spring, a safety member arranged to counteract the action of the cocking spring of the firing pin and to keep the safety guard lever in its position so as to prevent the firing pin from impacting the priming composition, said safety member being removable to release the firing in and the safety guard lever, and a locking spring member provided between the firing pin and the safety guard lever, said locking spring member, when released, swinging in opposite direction to the movement of the firing pin and the safety guard lever, said locking spring member being under pre-tension and releasing the firing pin only after causing the safety guard lever to swing by at least about about its axis of attachment to the top part of the projectile.

2. The rocker arm ignitin device according to claim 1, wherein the locking spring member is provided under pretension so as to release the firing pin only after causing the safety guard lever to swing by more than about its axis of attachment to the top part of the projectile.

3. The rocker arm igniting device according to claim 1, wherein the locking spring member is provided at its point of rotation with a lug member, said lug member being freely movably inserted into a bore hole of the top part of the ignition device.

4. The rocker arm igniting device according to claim 1, wherein the locking spring member is bent upwardly at its free end and cooperates with the edge of a recess of the safety guard lever.

References Cited UNITED STATES PATENTS 2,562,928 8/1951 Lewis 102-64 X 2,737,116 3/1956 Manzolini 102-64 3,072,056 1/1963 Kollmeyer et al 102-64 BENJAMIN A. BORCHELT, Primary Examiner.

G. H. GLANZMAN, Assistant Examiner. 

